Effect of Hufnagel Valve on Susceptibility of Dogs to Endocarditis

Endocarditis is a frequent and serious problem in patients with aortic insufficiency.¹ This problem may be approached experimentally by using dogs with aortic insufficiency,² which are highly susceptible to endocarditis.^3-5 Infections resembling acute and subacute bacterial endocarditis have been produced consistently in such dogs by either single or multiple intravenous injections of cultures of Staphylococcus aureus (Micrococcus pyogenes var. aureus) or Streptococcus mitis. In addition, the dogs given S. mitis often developed a diffuse proliferative glomerulonephritis, similar to that associated with human endocarditis.⁴ The present study was undertaken to determine whether a Hufnagel valve, by reducing the cardiac work load, would lessen the susceptibility of dogs with aortic insufficiency to endocarditis and glomerulonephritis.

Methods  Moderately severe aortic insufficiency was induced in 10 healthy mongrel dogs, weighing 10 to 20 kg., by perforating the right aortic leaflet with a punch introduced via the ascending aorta.² The